Molecular detection and genetic diversity of Rickettsia spp. in pet dogs and their infesting ticks in Harbin, northeastern China.

BACKGROUND: Pet dogs are important companion animals that share the environment within households, and play an important role in local community life. In addition, pet dogs also are reservoirs of zoonotic agents, including Rickettsia spp., thus increasing the risk of rickettsial infections in humans. It's meaningful to investigate the epidemiology of rickettsial agents in pet dogs, and make contribute to the surveillance of rickettsioses in human in China. RESULTS: In this study, a total of 496 pet dogs' blood samples and 343 ticks infested in pet dogs were collected, and the presence and prevalence of Rickettsia were determined by amplifying the partial gltA and 17-kDa genes, with an overall positive rate of 8.1 % in blood samples and 14.0 % in tick samples. In addition, the rrs, gltA, groEL, and ompA genes of rickettsial were also recovered to determine the species of Rickettsia detected furtherly. Sequencing blast and phylogenetic analyses revealed the presence of three human pathogenic Rickettsia species (Rickettsia raoultii, Candidatus Rickettsia tarasevichiae and Rickettsia felis) in samples associated with pet dogs. Moreover, all the sequences of Rickettsia that we obtained presented close relationship with others available in GenBank, and Rickettsia raoultii was the most predominant Rickettsia species infected in pet dogs' blood samples or in tick samples. CONCLUSIONS: This study provides the molecular epidemiology data about the Rickettsia spp. infection associated with pet dogs in urban areas of Harbin city. Three rickettisae species pathogenic to humans were identified from pet dogs' blood and the infested ticks in urban areas of Harbin city. Considering the intimate relationship between human and pets, these results indicate the potential transmission risk of human rickettisal infections from pet dogs through ectoparasites, and also highlighting that more attention should be paid to rickettsial infection in pet dogs and the infested ticks from the "One health" perspective.

[Effect of Guanxin Danshen Formulation on diabetic kidney disease in db/db mice through regulation of Nrf2 pathway].

Diabetic kidney disease(DKD) has become a primary cause of end-stage kidney disease, without any effective treatment available. In this study, we assessed the protective effect of Guanxin Danshen Formulation(GXDSF) on diabetic nephropathy in db/db mice. The db/m and db/db mice were randomly divided into 4 groups: control group, model group, metformin group, and GXDSF group. After 8 weeks' treatment with GXDSF, metformin or normal saline, the mice were sacrificed, and the blood and kidney tissues were collected for the further analysis. Compared with the model group, TG, TCH and LDL levels significantly decreased in the GXDSF group. The results from HE and PAS staining showed that db/db mice exhibited abnormal kidney tissues with increased glomerular volume, basement-membrane thickening and mesangial cell proliferation, which could be significantly alleviated by GXDSF treatment. GXDSF treatment also reduced serum creatinine and BUN. Meanwhile, GXDSF treatment markedly elevated GSH-PX levels, while reduced LDH and MDA levels in the kidney tissues. Western blot assay showed that GXDSF evidently up-regulated protein levels of ERα and p-Akt, and subsequently promoted HO-1 expression mediated by Nrf2. These data collectively indicated that GXDSF protects db/db mice against DN by regulating ERα and Nrf2-mediated HO-1 expression.

Molecular evidence of Babesia in pet cats in mainland China.

BACKGROUND: Babesia spp. are important emerging tick-borne protozoan hemoparasites, and pose a great impact on companion animals. Canine babesiosis has been well described worldwide, while felis babesiosis has primarily been reported from South Africa. To the best of our knowledge, Babesia spp. infections in dogs have been well elucidated in pet dog population in China, no report about Babesia spp. infection in cat population in mainland China. RESULTS: In this study, a total of 203 blood samples were collected from pet cats in Shenzhen city, and detected the presence of Babesia spp. with nested-PCR. Sequence comparison based on the 18S rRNA gene and ITS region revealed that three cats (1.48%) were infected with Babesia. vogeli. Notably, the sequences of ITS region obtained in this study shared the highest nucleotide identity with the sequence of B. vogeli strain isolated in cat from Taiwan. CONCLUSIONS: This study is the first report about babesiosis in domestic cats, and also provides molecular evidence of Babesia spp. infection in cat in mainland China. The data present in this study suggest B. vogeli may be circulating in cat population in mainland China. Further study to investigate the epidemiology of Babesia infection in cat nationwide is warranted.

Meta-transcriptomic analysis reveals a new subtype of genotype 3 avian hepatitis E virus in chicken flocks with high mortality in Guangdong, China.

BACKGROUND: Hepatitis E virus (HEV) is one of most important zoonotic viruses, and it can infect a wide range of host species. Avian HEV has been identified as the aetiological agent of big liver and spleen disease or hepatitis-splenomegaly syndrome in chickens. HEV infection is common among chicken flocks in China, and there are currently no practical measures for preventing the spread of the disease. The predominant avian HEV genotype circulating in China have been identified as genotype 3 strains, although some novel genotypes have also been identified from chicken flocks in China. RESULTS: In this study, we used a meta-transcriptomics approach to identify a new subtype of genotype 3 avian HEV in broiler chickens at a poultry farm located in Shenzhen, Guangdong Province, China. The complete genome sequence of the avian HEV, designated CaHEV-GDSZ01, is 6655-nt long, including a 5' UTR of 24 nt and a 3' UTR of 125 nt (excluding the poly(A) tail), and contains three open reading frames (ORFs). Sequence analysis indicated that the complete ORF1 (4599 nt/1532 aa), ORF2 (1821 nt/606 aa) and ORF3 (264 nt/87 aa) of CaHEV-GDSZ01 share the highest nucleotide sequence identity (85.8, 86.7 and 95.8%, respectively) with the corresponding ORFs of genotype 3 avian HEV. Phylogenetic analyses further demonstrated that the avian HEV identified in this study is a new subtype of genotype 3 avian HEV. CONCLUSIONS: Our results demonstrate that a new subtype of genotype 3 avian HEV is endemic in Guangdong, China, and could cause high mortality in infected chickens. This study also provides full genomic data for better understanding the evolutionary relationships of avian HEV circulating in China. Altogether, the results presented in this study suggest that more attention should be paid to avian HEV and its potential disease manifestation.

Molecular characterization of two novel reoviruses isolated from Muscovy ducklings in Guangdong, China.

BACKGROUND: Novel Muscovy duck reovirus (N-MDRV), emerged in southeast China in 2002, which can infect a wide range of waterfowl and induces clinical signs and cytopathic effects that are distinct from those of classical MDRV, and continues to cause high morbidity and 5-50% mortality in ducklings. The present study aimed to investigate the characteristics of two novel reoviruses isolated from Muscovy ducklings in Guangdong, China. RESULTS: Two novel MDRV strains, designated as MDRV-SH12 and MDRV-DH13, were isolated from two diseased Muscovy ducklings in Guangdong province, China in June 2012 and September 2013, respectively. Sequencing of the complete genomes of these two viruses showed that they consisted of 23,418 bp and were divided into 10 segments, ranging from 1191 bp (S4) to 3959 bp (L1) in length, and all segments contained conserved sequences in the 5' non-coding region (GCUUUU) and 3' non-coding region (UCAUC). Pairwise sequence comparisons demonstrated that MDRV-SH12 and MDRV-DH13 showed the highest similarity with novel MDRVs. Phylogenetic analyses of the nucleotide sequences of all 10 segments revealed that MDRV-SH12 and MDRV-DH13 were clustered together with other novel waterfowl-origin reoviruses and were distinct from classical waterfowl-origin and chicken-origin reoviruses. The analyses also showed possible genetic re-assortment events in segment M2 between waterfowl-origin and chicken-origin reoviruses and the segments encoding λA, µA, µNS, σA, and σNS between classical and novel waterfowl-origin reoviruses. Potential recombination events detection in segment S2 suggests that MDRV-SH12 and MDRV-DH13 may be recombinants of classical and novel WRVs. CONCLUSIONS: The results presented in this study, the full genomic data for two novel MDRV strains, will improve our understanding of the evolutionary relationships among the waterfowl-origin reoviruses circulating in China, and may aid in the development of more effective vaccines against various waterfowl-origin reoviruses.

Angiotensin-converting enzyme 2 regulates mitochondrial function in pancreatic ß-cells.

Mitochondrial metabolism plays an essential role in the regulation of insulin release and glucose homeostasis. Evidence demonstrated that the angiotensin-converting enzyme 2 (ACE2) participates in the regulation of glucose metabolism, however, its role in mitochondrial metabolism remains unclear. The purpose of our study was to determine if ACE2 can regulate mitochondrial function in pancreatic ß-cells. We found that ACE2 over-expression restored glucose-stimulated insulin secretion (GSIS) and mitochondrial membrane potential (MMP) in the presence of H2O2 in INS-1 cells. PCR array demonstrated that ACE2 over-expression up-regulated 67 mitochondria-related genes in INS-1 cells. In pancreatic islets, ACE2 ablation attenuated intracellular calcium influx with a decrease in GSIS. Ace2-/y mice islets exhibited impaired mitochondrial respiration and lower production of ATP, along with decreased expression of genes involved in mitochondrial oxidation. In islets from db/db mice, ACE2 over-expression increased intracellular calcium influx and restored impaired mitochondrial oxidation, potentially causing an increase in GSIS. These results shed light on the potential roles of ACE2 in mitochondrial metabolism, moreover, may improve our understanding of diabetes.

Efficient replication of blood-borne hepatitis C virus in human fetal liver stem cells.

The development of pathogenic mechanisms, specific antiviral treatments and preventive vaccines for hepatitis C virus (HCV) infection has been limited due to lack of cell culture models that can naturally imitate the entire HCV life cycle. Here, we established an HCV cell culture model based on human fetal liver stem cells (hFLSCs) that supports the entire blood-borne hepatitis C virus (bbHCV) life cycle. More than 90% of cells remained infected by various genotypes. bbHCV was efficiently propagated, and progeny virus were infectious to hFLSCs. The virus could be passed efficiently between cells. The viral infectivity was partially blocked by specific antibodies or small interfering RNA against HCV entry factors, whereas HCV replication was inhibited by antiviral drugs. We observed viral particles of approximately 55 nm in diameter in both cell culture media and infected cells after bbHCV infection. CONCLUSION: Our data show that the entire bbHCV life cycle could be naturally imitated in hFLSCs. This model is expected to provide a powerful tool for exploring the process and the mechanism of bbHCV infection at the cellular level and for evaluating the treatment and preventive strategies of bbHCV infection. (Hepatology 2017;66:1045-1057).

An Intracellular Laccase Is Responsible for Epicatechin-Mediated Anthocyanin Degradation in Litchi Fruit Pericarp.

In contrast to the detailed molecular knowledge available on anthocyanin synthesis, little is known about its catabolism in plants. Litchi (Litchi chinensis) fruit lose their attractive red color soon after harvest. The mechanism leading to quick degradation of anthocyanins in the pericarp is not well understood. An anthocyanin degradation enzyme (ADE) was purified to homogeneity by sequential column chromatography, using partially purified anthocyanins from litchi pericarp as a substrate. The purified ADE, of 116 kD by urea SDS-PAGE, was identified as a laccase (ADE/LAC). The full-length complementary DNA encoding ADE/LAC was obtained, and a polyclonal antibody raised against a deduced peptide of the gene recognized the ADE protein. The anthocyanin degradation function of the gene was confirmed by its transient expression in tobacco (Nicotiana benthamiana) leaves. The highest ADE/LAC transcript abundance was in the pericarp in comparison with other tissues, and was about 1,000-fold higher than the polyphenol oxidase gene in the pericarp. Epicatechin was found to be the favorable substrate for the ADE/LAC. The dependence of anthocyanin degradation by the enzyme on the presence of epicatechin suggests an ADE/LAC epicatechin-coupled oxidation model. This model was supported by a dramatic decrease in epicatechin content in the pericarp parallel to anthocyanin degradation. Immunogold labeling transmission electron microscopy suggested that ADE/LAC is located mainly in the vacuole, with essential phenolic substances. ADE/LAC vacuolar localization, high expression levels in the pericarp, and high epicatechin-dependent anthocyanin degradation support its central role in pigment breakdown during pericarp browning.

[Intervention of Qingshen Granule for Immune Inflammation of Chronic Renal Failure Patients with Damp-heat Syndrome].

Objective To observe the effect of Qingshen Granule (QG) on the immune function of chronic renal failure (CRF) patients with damp-heat syndrome (DHS). Methods A total of 162 CRF patients were assigned to the treated group and the control group by random digit table, 81 in each group. All patients were treated with conventional Western medical therapy. Those in the treated group addition- ally took QG, one package each time (10 g) , thrice per day. The therapeutic course for all was 12 weeks. The clinical efficacy was observed in the two groups. The contents of peripheral blood CD4 ⁺ T cells, CD8 ⁺ T cells, Thl7 cells, and nuclear factor-κB p65 (NF-κBp65) activity were detected using flow cy- tometry. Expressions of serum IL-17, tumor necrosis factor receptor-associated factor 6 (TRAF6), ma- trix metalloproteinase-9 (MMP-9) , matrix metalloproteinase inhibitor-I (TIMP-1 ) , collagen N (Col-V) were detected using ELISA. Results Finally 156 patients completed the trial (77 cases in the treated group and 79 cases in the control group). The total clinical curative effective rate was significantly higher in the treated group (80. 52%, 62/77) than in the control group (68. 35%, 54/79) with statistical differ- ences between the two groups (x² = 54. 849, P <0. 05). Compared with before treatment in the same group, the levels of peripheral blood CD4 ⁺ /CD8 ⁺ , Thl7 cell content, NF-κB p65 activity, serum levels of IL-17, TRAF6, and TIMP-1 , TIMP-1/MMP-9 ratio, Col-IV level all decreased in the treated group after treat- ment (P <0. 05) ; serum MMP-9 level decreased .(P <0. 05) and TIMP-1 /MMP-9 ratio increased (P <0. 05) in the control group. Compared with the control group, CD4⁺/CD8 ⁺ T cell ratio, Th17 cell content, NF-κB p65 activity decreased more obviously in the treated group after treatment (P <0. 05). Serum levels of IL- 17, TRAF6, TIMP-1, TIMP-1/MMP-9 ratio, and Col-IV all decreased (P <0.05) and MMP-9 level increased (P <0. 05) in the treated group (P <0. 05). Conclusion QG could adjust immune dysfunction and disar- ranged immunity mediated inflammatory response, and attenuate renal fibrosis in CKD patients with DHS.

[Sesquiterpenes of Chloranthus serratus Root].

OBJECTIVE: To study sesquiterpenes from the root of Chloranthus serratus. METHODS: The sesquiterpenes of Chloranthus serratus were isolated and purified by various chromatographic techniques, such as silica gel, Sephadex LH-20 and preparative HPLC. The structures of these isolated compounds were identified by spectroscopic analysis. RESULTS: Ten sesquiterpenes were isolated and identified as follows: 1ß, 8ß-dihydroxy-eudesman-4 (15), 7 (11) -dien-8α, 12-olide (I), curcolonol (II), 4ß, 8ß-dihydroxy-5α (H) -eudesm-7 (11) -en-8, 12-olide (III), 1ß, 8,ß-dihydroxy-eudesman-3, 7 (11) -dien-8α, 12-olide (IV), multistalactone E (V), zedoarofuran (VI), 8ß,9α-dihydroxylindan-4(5), 7(11) -dien-8α,12-olide(VII), serralactone A (VIII), 8-epi-ivangustin (IX), and chloranthalactone E (X ). CONCLUSION: Compounds I, II, IV - VII, IX and X are isolated from Chloranthus serratus for the first time.

Age-specific differences in the association between prediabetes and cardiovascular diseases in China: A national cross-sectional study.

BACKGROUND: Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide, the global burden of which is rising. It is still unclear the extent to which prediabetes contributes to the risk of CVD in various age brackets among adults. To develop a focused screening plan and treatment for Chinese adults with prediabetes, it is crucial to identify variations in the connection between prediabetes and the risk of CVD based on age. AIM: To examine the clinical features of prediabetes and identify risk factors for CVD in different age groups in China. METHODS: The cross-sectional study involved a total of 46239 participants from June 2007 through May 2008. A thorough evaluation was conducted. Individuals with prediabetes were categorized into two groups based on age. Chinese atherosclerotic CVD risk prediction model was employed to evaluate the risk of developing CVD over 10 years. Random forest was established in both age groups. SHapley Additive exPlanation method prioritized the importance of features from the perspective of assessment contribution. RESULTS: In total, 6948 people were diagnosed with prediabetes in this study. In pre-diabetes, prevalences of CVD were 5 (0.29%) in the younger group and 148 (2.85%) in the older group. Overall, 11.11% of the younger group and 29.59% of the older group were intermediate/high-risk of CVD for prediabetes without CVD based on the Prediction for ASCVD Risk in China equation in ten years. In the younger age group, the 10-year risk of CVD was found to be more closely linked to family history of CVD rather than lifestyle, whereas in the older age group, resident status was more closely linked. CONCLUSION: The susceptibility to CVD is age-specific in newly diagnosed prediabetes. It is necessary to develop targeted approaches for the prevention and management of CVD in adults across various age brackets.

Effects of temporal changes in resting heart rate on future diabetes-related outcomes.

Background and aims: Most studies have analyzed the relationship between resting heart rate (RHR) measured at only one time point and future clinical events. The current study aims to investigate the impact of long-term RHR changes on future clinical outcomes in a decade-long cohort with type 2 diabetes mellitus (T2DM). Methods: The two-staged follow-up involved 2,513 T2DM participants. The first stage (2008-2014) intended to identify levels and trends in RHR changes, while the second stage (2014-2018) attempted to collect new occurrence records of clinical results. Cox proportional hazards models were applied to predict hazard ratios (HRs), along with 95% confidence interval (CI) for the correlation between RHR changes and future events. Results: There is no significant correlation between baseline RHR levels and long-term clinical events. According to the range of RHR change, compared with the stable RHR group, the adjusted HRs for cardiovascular events and all-cause death in the large increase group were 3.40 (95% CI: 1.33-8.71, p=0.010) and 3.22 (95% CI: 1.07-9.64, p=0.037), respectively. While the adjusted HRs for all-cause death and major adverse cardiac and cerebrovascular events (MACCE) in the moderate decrease group were 0.55 (95% CI: 0.31-0.96, p=0.037) and 0.51 (95% CI: 0.26-0.98, p=0.046). According to the trend of RHR, compared with the normal-normal group, the adjusted HRs for composite endpoint events and cerebrovascular events in the normal-high group were 1.64 (95% CI: 1.00-2.68, p=0.047) and 2.82 (95% CI: 1.03-7.76, p=0.043), respectively. Conclusion: Changes in RHR had predictive value for long-term clinical events in diabetic populations. Individuals with significantly elevated RHR over a particular period of time showed an increased risk of adverse events.

The residues and environmental risks of multiple veterinary antibiotics in animal faeces.

To understand the residues and ecological risks of veterinary antibiotics (VAs) in animal faeces from concentrated animal feeding operations in northeastern China, 14 VAs were identified by high performance liquid chromatography, and the preliminary risks of six antibiotics were assessed using the hazard quotient (HQ). The investigated VAs occurred in 7.41 to 57.41 % of the 54 samples, and the levels ranged from 0.08 to 56.81 mg kg(-1). Tetracyclines were predominant with a maximum level of 56.81 mg kg(-1) mostly detected in pig faeces. Sulfonamides were common and detected with the highest concentration of 7.11 mg kg(-1). Fluoroquinolones were more widely detected in chicken faeces rather than in pig or cow faeces, which contained the dominant antibiotic enrofloxacin. In comparison, the residue of tylosin was less frequently found. The risk evaluations of the six antibiotics revealed that tetracyclines, especially oxytetracycline, displayed the greatest ecological risk because of its high HQ value of 15.75. The results of this study imply that multiple kinds of VAs were jointly used in animal feeding processes in the study area. These medicine residues in animal faeces may potentially bring ecological risks if the animal manure is not treated effectively.

Molecular detection and genetic characterization of bovine hepacivirus identified in ticks collected from cattle in Harbin, northeastern China.

Bovine hepacivirus (BovHepV) is a member of the genus Hepacivirus of the family Flaviviridae, which can cause acute or persistent infections in cattle. Currently, BovHepV strains identified in cattle populations worldwide can be classified into two genotypes with eight subtypes in genotype 1. BovHepV has been identified in a wide geographic area in China. Interestingly, the viral RNA of BovHepV has also been detected in ticks in Guangdong province, China. In this study, Rhipicephalus microplus tick samples were collected in Heilongjiang province, northeastern China, and BovHepV was screened with an overall positive rate of 10.9%. Sequence comparison and phylogenetic analysis showed that the BovHepV strains detected in this study belong to the subtype G. This is the first report about the detection of BovHepV in ticks in Heilongjiang province, China, which expands our knowledge that ticks may be a transmission vector of BovHepV.

Epidemiology and genotypic diversity of canine circovirus identified in pet dogs in Harbin, China.

Canine circovirus (CanineCV) is a single-stranded DNA virus that circulates in dogs and wild carnivores around the world. It has been suggested to be associated with diseases of respiratory and gastrointestinal systems, though its pathogenic potential remains unclear. Currently, CanineCV is divided into six genotypes (genotype 1-6), and genotypes 2, 3, and 4 have been described in China. In this study, 359 blood samples from pet dogs with or without clinical signs were collected in Harbin city. After PCR screening, a total of 34 samples were tested positive for CanineCV, and nine full-length genome sequences were recovered from positive samples. Pairwise sequence comparison showed that they shared 82.4-99.3% genome-wide identity with other CanineCVs available in GenBank. Additionally, recombination events were detected, all of which were determined to be associated with sequences obtained in China. The reconstructed phylogenetic tree based on the recombination-free complete genome sequences revealed that the complete genome sequences generated herein were clustered into genotypes 1 and 3. Furthermore, purifying selection was the dominant evolutionary pressure acting on the genomes of CanineCV. These results expand the knowledge about the genetic diversity of CanineCV circulating in China, and also promote us to better understand the evolution of CanineCV.

A Highly Divergent Hepacivirus Identified in Domestic Ducks Further Reveals the Genetic Diversity of Hepaciviruses.

Hepaciviruses represent a group of viruses that pose a significant threat to the health of humans and animals. During the last decade, new members of the genus Hepacivirus have been identified in various host species worldwide, indicating the widespread distribution of genetically diversified hepaciviruses among animals. By applying unbiased high-throughput sequencing, a novel hepacivirus, provisionally designated Hepacivirus Q, was discovered in duck liver samples collected in Guangdong province of China. Genetic analysis revealed that the complete polyprotein of Hepacivirus Q shares 23.9-46.6% amino acid identity with other representatives of the genus Hepacivirus. Considering the species demarcation criteria for hepaciviruses, Hepacivirus Q should be regarded as a novel hepacivirus species of the genus Hepacivirus within the family Flaviviridae. Phylogenetic analyses also indicate the large genetic distance between Hepacivirus Q and other known hepaciviruses. Molecular detection of this novel hepacivirus showed an overall prevalence of 15.9% in duck populations in partial areas of Guangdong province. These results expand knowledge about the genetic diversity and evolution of hepaciviruses and indicate that genetically divergent hepaciviruses are circulating in duck populations in China.

Epidemiology and Genetic Diversity of Bartonella in Rodents in Urban Areas of Guangzhou, Southern China.

Bartonella spp. are gram-negative bacteria that can infect a wide spectrum of mammals. Rodents are considered to be the natural reservoir of many Bartonella species that are transmitted by various blood-sucking arthropods. The close contact between rodents and humans in urban areas increased the chance of transmitting rodent-borne Bartonella to humans. Investigation of the epidemiological characteristics of Bartonella infection in rodents is of great significance for the prevention and control of human Bartonellosis. In this study, rodents were captured to monitor the prevalence of Bartonella in urban areas of Guangzhou city. Six official or candidate species of Bartonella, including two confirmed zoonotic species, were detected with an overall prevalence of 6.4% in rodents captured herein. In addition, Rattus norvegicus was the predominant host species for Bartonella infection, and B. queenslandensis was the dominant species circulating in rodents in these areas. These results provide insights into the prevalence and genetic diversity of Bartonella species circulating in rodents in the urban areas of Guangzhou, and also urged the surveillance of rodent-associated Bartonella species in these areas.

Extensive genetic diversity and recombination events identified in goose circoviruses circulating in partial areas of Guangdong province, Southern China.

Circoviruses represent a group of small viruses with circular single-strand DNA genome that infect a wide range of both domesticated and wild animals. Domesticated geese infected with circovirus have been confirmed in many parts of the world, and is considered to cause immunosuppression and facilitate the secondary infections caused by other pathogens. In the present study, extensive genetically diversified goose circoviruses (GoCVs) were identified in the liver samples of domesticated geese from Guangdong province, southern China. Genetic analysis revealed that the sequences generated in this study shared 81.5 to 99.7% genome-wide pairwise identity with previously identified GoCV genomes. More importantly, nine recombination events were identified among all known complete genomome sequences of GoCV including those obtained herein, and the majority was determined associate with the sequences identified from Guangdong province, suggesting that recombination is the primary driver for the diversification of GoCVs. Additionally, purifying selection was the dominant evolutionary pressure acting on the genomes of GoCVs, and the ORF C1 gene of GoCV showed a higher genetic variation than ORF V1 gene. These results expand the knowledge about the genetic diversity and evolution of GoCV, and also indicate extensive genetically divergent GoCV strains were co-circulating in goose population in partial areas of Guangdong province, southern China.

Angiotensin(1-7) activates MAS-1 and upregulates CFTR to promote insulin secretion in pancreatic ß-cells: the association with type 2 diabetes.

Objective: The beneficial effect of angiotensin(1-7) (Ang(1-7)), via the activation of its receptor, MAS-1, has been noted in diabetes treatment; however, how Ang(1-7) or MAS-1 affects insulin secretion remains elusive and whether the endogenous level of Ang(1-7) or MAS-1 is altered in diabetic individuals remains unexplored. We recently identified an important role of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl- channel, in the regulation of insulin secretion. Here, we tested the possible involvement of CFTR in mediating Ang(1-7)'s effect on insulin secretion and measured the level of Ang(1-7), MAS-1 as well as CFTR in the blood of individuals with or without type 2 diabetes. Methods: Ang(1-7)/MAS-1/CFTR pathway was determined by specific inhibitors, gene manipulation, Western blotting as well as insulin ELISA in a pancreatic ß-cell line, RINm5F. Human blood samples were collected from 333 individuals with (n = 197) and without (n = 136) type 2 diabetes. Ang(1-7), MAS-1 and CFTR levels in the human blood were determined by ELISA. Results: In RINm5F cells, Ang(1-7) induced intracellular cAMP increase, cAMP-response element binding protein (CREB) activation, enhanced CFTR expression and potentiated glucose-stimulated insulin secretion, which were abolished by a selective CFTR inhibitor, RNAi-knockdown of CFTR, or inhibition of MAS-1. In human subjects, the blood levels of MAS-1 and CFTR, but not Ang(1-7), were significantly higher in individuals with type 2 diabetes as compared to those in non-diabetic healthy subjects. In addition, blood levels of MAS-1 and CFTR were in significant positive correlation in type-2 diabetic but not non-diabetic subjects. Conclusion: These results suggested that MAS-1 and CFTR as key players in mediating Ang(1-7)-promoted insulin secretion in pancreatic ß-cells; MAS-1 and CFTR are positively correlated and both upregulated in type 2 diabetes.

Research note: genetic diversity of duck circoviruses circulating in partial areas of Guangdong province, southern China.

Duck circovirus (DuCV) is the smallest known virus in waterfowl that infects both domestic and wild duck. Infected ducks often show stunted growth and immunosuppression, which increases the rate of secondary infection with other pathogens. In this study, 270 liver tissue samples were collected to screen the presence of DuCV in Guangdong province, China, and the complete genome sequences were recovered and systematically analyzed. Genetic analyses revealed that sequences determined in this study shared 81.6% to 100.0% genome-wide pairwise identity with previously identified DuCV genomes. Phylogenetic analyses showed that 2 DuCV genotypes with a high infection rate were co-circulating in duck population in Guangdong province, and extensive recombination events have occurred during the evolution of DuCV. Our results expand upon the knowledge regarding the genetic diversity and evolution of DuCV, and also indicate that extensive genetically divergent DuCV are co-circulating in the duck populations in Guangdong, southern China.